/*
 Stream.cpp - adds parsing methods to Stream class
 Copyright (c) 2008 David A. Mellis.  All right reserved.

 This library is free software; you can redistribute it and/or
 modify it under the terms of the GNU Lesser General Public
 License as published by the Free Software Foundation; either
 version 2.1 of the License, or (at your option) any later version.

 This library is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 Lesser General Public License for more details.

 You should have received a copy of the GNU Lesser General Public
 License along with this library; if not, write to the Free Software
 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

 Created July 2011
 parsing functions based on TextFinder library by Michael Margolis
 Modified August 2016 by Marcelo Aquino <marceloaqno@gmail.org> for MySensors use
 */

#include <Arduino.h>
#include <Stream.h>

#define PARSE_TIMEOUT 1000  // default number of milli-seconds to wait
#define NO_SKIP_CHAR  1  // a magic char not found in a valid ASCII numeric field

// private method to read stream with timeout
int Stream::timedRead()
{
	_startMillis = millis();
	do {
		int c;
		c = read();
		if(c >= 0) {
			return c;
		}
		yield();
	} while(millis() - _startMillis < _timeout);
	return -1;     // -1 indicates timeout
}

// private method to peek stream with timeout
int Stream::timedPeek()
{
	_startMillis = millis();
	do {
		int c;
		c = peek();
		if(c >= 0) {
			return c;
		}
		yield();
	} while(millis() - _startMillis < _timeout);
	return -1;     // -1 indicates timeout
}

// returns peek of the next digit in the stream or -1 if timeout
// discards non-numeric characters
int Stream::peekNextDigit()
{
	while(1) {
		int c;
		c = timedPeek();
		if(c < 0) {
			return c;  // timeout
		}
		if(c == '-') {
			return c;
		}
		if(c >= '0' && c <= '9') {
			return c;
		}
		read();  // discard non-numeric
	}
}

// Public Methods
//////////////////////////////////////////////////////////////

void Stream::setTimeout(unsigned long timeout)  // sets the maximum number of milliseconds to wait
{
	_timeout = timeout;
}

// find returns true if the target string is found
bool Stream::find(const char *target)
{
	return findUntil(target, (char*) "");
}

// reads data from the stream until the target string of given length is found
// returns true if target string is found, false if timed out
bool Stream::find(const char *target, size_t length)
{
	return findUntil(target, length, NULL, 0);
}

// as find but search ends if the terminator string is found
bool Stream::findUntil(const char *target, const char *terminator)
{
	return findUntil(target, strlen(target), terminator, strlen(terminator));
}

// reads data from the stream until the target string of the given length is found
// search terminated if the terminator string is found
// returns true if target string is found, false if terminated or timed out
bool Stream::findUntil(const char *target, size_t targetLen, const char *terminator,
                       size_t termLen)
{
	size_t index = 0;  // maximum target string length is 64k bytes!
	size_t termIndex = 0;
	int c;

	if(*target == 0) {
		return true;   // return true if target is a null string
	}
	while((c = timedRead()) > 0) {

		if(c != target[index]) {
			index = 0; // reset index if any char does not match
		}
		if(c == target[index]) {
			//////Serial.print("found "); Serial.write(c); Serial.print("index now"); Serial.println(index+1);
			if(++index >= targetLen) { // return true if all chars in the target match
				return true;
			}
		}

		if(termLen > 0 && c == terminator[termIndex]) {
			if(++termIndex >= termLen) {
				return false;       // return false if terminate string found before target string
			}
		} else {
			termIndex = 0;
		}
	}
	return false;
}

// returns the first valid (long) integer value from the current position.
// initial characters that are not digits (or the minus sign) are skipped
// function is terminated by the first character that is not a digit.
long Stream::parseInt()
{
	return parseInt(NO_SKIP_CHAR); // terminate on first non-digit character (or timeout)
}

// as above but a given skipChar is ignored
// this allows format characters (typically commas) in values to be ignored
long Stream::parseInt(char skipChar)
{
	bool isNegative = false;
	long value = 0;
	int c;

	c = peekNextDigit();
	// ignore non numeric leading characters
	if(c < 0) {
		return 0; // zero returned if timeout
	}

	do {
		if(c == skipChar) {
			// ignore this charactor
		} else if(c == '-') {
			isNegative = true;
		} else if(c >= '0' && c <= '9') {     // is c a digit?
			value = value * 10 + c - '0';
		}
		read();  // consume the character we got with peek
		c = timedPeek();
	} while((c >= '0' && c <= '9') || c == skipChar);

	if(isNegative) {
		value = -value;
	}
	return value;
}

// as parseInt but returns a floating point value
float Stream::parseFloat()
{
	return parseFloat(NO_SKIP_CHAR);
}

// as above but the given skipChar is ignored
// this allows format characters (typically commas) in values to be ignored
float Stream::parseFloat(char skipChar)
{
	bool isNegative = false;
	bool isFraction = false;
	long value = 0;
	int c;
	float fraction = 1.0;

	c = peekNextDigit();
	// ignore non numeric leading characters
	if(c < 0) {
		return 0; // zero returned if timeout
	}

	do {
		if(c == skipChar) {
			// ignore
		} else if(c == '-') {
			isNegative = true;
		} else if(c == '.') {
			isFraction = true;
		} else if(c >= '0' && c <= '9') {    // is c a digit?
			value = value * 10 + c - '0';
			if(isFraction) {
				fraction *= 0.1;
			}
		}
		read();  // consume the character we got with peek
		c = timedPeek();
	} while((c >= '0' && c <= '9') || c == '.' || c == skipChar);

	if(isNegative) {
		value = -value;
	}
	if(isFraction) {
		return value * fraction;
	} else {
		return value;
	}
}

// read characters from stream into buffer
// terminates if length characters have been read, or timeout (see setTimeout)
// returns the number of characters placed in the buffer
// the buffer is NOT null terminated.
//
size_t Stream::readBytes(char *buffer, size_t length)
{
	size_t count = 0;
	while(count < length) {
		int c = timedRead();
		if(c < 0) {
			break;
		}
		*buffer++ = (char) c;
		count++;
	}
	return count;
}

// as readBytes with terminator character
// terminates if length characters have been read, timeout, or if the terminator character  detected
// returns the number of characters placed in the buffer (0 means no valid data found)

size_t Stream::readBytesUntil(char terminator, char *buffer, size_t length)
{
	if(length < 1) {
		return 0;
	}
	size_t index = 0;
	while(index < length) {
		int c = timedRead();
		if(c < 0 || c == terminator) {
			break;
		}
		*buffer++ = (char) c;
		index++;
	}
	return index; // return number of characters, not including null terminator
}

std::string Stream::readString()
{
	std::string ret;
	int c = timedRead();
	while(c >= 0) {
		ret += (char) c;
		c = timedRead();
	}
	return ret;
}

std::string Stream::readStringUntil(char terminator)
{
	std::string ret;
	int c = timedRead();
	while(c >= 0 && c != terminator) {
		ret += (char) c;
		c = timedRead();
	}
	return ret;
}
